Rquirements for Tea Raw Materials
(1) Tea Must Be Fully Dried
Moisture acts as an essential medium for all biochemical reactions inside tea leaves, the primary cause of tea mildew, and a necessary condition for microbial reproduction. Extensive research shows that for packaged stored tea: If the moisture content exceeds 6.5%, stale off-flavors will develop after six months of storage, and higher moisture accelerates aging; When moisture rises above 7%, the tea taste gradually deteriorates; At 8.8%, mold growth is highly likely; Once exceeding 12%, molds multiply drastically and a distinct mildew odor emerges. Under standard conditions, the moisture content of packaged tea shall be controlled below 6%, with a maximum limit of 7%.
(2) Normal Tea Quality
The tea shall maintain intact quality without deterioration, foreign odors or non-tea impurities.
Requirements for Packaging Materials Packaging materials refer to raw materials used for manufacturing commodity packages, covering materials for production, storage, transportation packaging as well as retail packaging.
A, No Harmful Substances to Human
Health Tea is consumed by steeping dried leaves in boiling water for a period, allowing soluble beneficial compounds to leach into the tea liquor, which people drink directly to absorb nutrients. Safety of raw materials shall be the top priority when selecting tea packaging. Only non-toxic, safe and reliable raw materials are allowed to produce tea packages, among which inner packaging materials are particularly critical. Key Industry Term Glossary
B, Satisfactory Chemical Stability
If tea packaging materials lack sufficient chemical stability, they will directly contaminate tea leaves during packaging, storage and transportation. For example, polyvinyl chloride (PVC), a polymer material, cannot be used directly as tea inner packaging. It releases hydrogen chloride gas during high-temperature heat sealing, contaminating tea and even causing lead pollution. Likewise, phenolic plastic and urea-formaldehyde plastic are unfit for tea packaging. They produce harmful substances such as phenol and formaldehyde under high-temperature heat sealing. Therefore, such polymer materials are forbidden for tea packaging.
C, Excellent Processability Tea packages serve dual purposes: preserving tea quality and beautifying & promoting products. Thus, materials with outstanding processing and printing performance are required to manufacture packages with high practical value and attractive promotional effects.
D, Superior Comprehensive Barrier Properties Tea packaging materials shall feature excellent gas barrier, moisture-proof and light-shielding properties. Tea leaves have loose and porous structures, making them extremely prone to moisture absorption and odor adsorption. Besides, light exposure will alter the color of high-grade green tea. Only packaging materials with excellent comprehensive barrier functions can effectively protect tea quality.
E, Reliable Protective Performance The materials shall provide stable and dependable protection to guarantee tea safety.
